The present invention relates to a mask structure used to manufacture a semiconductor device and a correction technique for the mask pattern. The present invention also relates to an exposure apparatus and a device manufacturing method using the correction technique. The present invention also relates to a mask pattern manufacturing method using the correction technique.
Lithography technologies using X-rays are attracting attention as techniques of forming especially fine patterns in semiconductor devices. In one of the schemes, a mask and wafer are closely arranged and irradiated with X-rays to realize one-to-one exposure/transfer. In this scheme, since the mask and wafer are closely arranged, and no reduction projecting optical system is present, the transfer magnification on the wafer cannot be adjusted.
To solve this problem, a (magnification correction) method of applying an external force to a mask structure to change the pattern size has been proposed, as disclosed in Japanese Patent Laid-Open No. 10-242033.
In this prior art, two abutting fixed members 258 and 259 are arranged in the directions of extended lines of two diagonal lines of the rectangular window of a mask structure, respectively, as shown in FIG. 15. Forces P1 and P2 toward the mask center are applied to positions opposite to the abutting fixed members, thereby correcting the magnification.
In the above prior art, an isotropic change in pattern can be obtained in the X- and Y-directions (square reducing modification). However, the magnification cannot be corrected by desired different amounts in the X- and Y-axis directions (rectangular reducing modification).
It is the first object of the present invention to provide a mask pattern magnification correction method which improves the prior art and makes it possible to correct a magnification by different amounts in the X- and Y-axis directions, thereby realizing more accurate overlay.
It is the second object of the present invention to provide a method of realizing the first object by a simpler mechanism or pressurizing method.
It is the third object of the present invention to provide a device manufacturing method which includes the step of transferring a mask pattern onto a wafer serving as a photosensitive substrate and can cope with mask pattern correction by different magnifications in the X- and Y-axis directions.
It is the fourth object of the present invention to provide a mask pattern manufacturing method of drawing a mask pattern while a membrane is being distorted by a predetermined force using a mask pattern magnification correction method according to the present invention.
It is the fifth object of the present invention to provide a mask structure to which a mask pattern magnification correction method according to the present invention is applied.
In order to solve the problem and achieve the objects, the first aspect of the present invention is characterized in that, for a mask structure which has a mask substrate on which a mask pattern is formed and a ring-shaped support frame having a rectangular window, forces are applied to four pressurizing points of an outer periphery of the support frame on substantially extended lines of two diagonal lines of the rectangular window, and an angle of a vector of each force is adjusted with respect to each of the pressurizing points.
In order to achieve the above objects, according to the second aspect of the present invention, the vector of the force is decomposed in the X- and Y-axis directions parallel to the sides of the rectangular window to pressurize the support frame, the force is applied to the support frame through a rolling contactable portion, some of the pressurizing points are set as fixed points, or for at least some of the fixed points, and a slide function is added to a receiving mechanism that receives the fixed point, thereby making the mechanism or pressurizing method more simple and easy to handle.
In order to achieve the above objects, the third aspect of the present invention is characterized in that the mask pattern magnification correction method of the present invention is used for a device manufacturing method comprising the mask pattern transfer step of transferring a mask pattern onto a photosensitive substrate in X-ray exposure or the like.
In order to achieve the above objects, the fourth aspect of the present invention is characterized in that the mask pattern magnification correction method of the present invention is used for a mask pattern manufacturing method in which a mask pattern is drawn using an electron beam or the like.
In order to achieve the above objects, a mask structure according to the fifth aspect of the present invention is characterized by comprising a mask substrate having a membrane on which a mask pattern is formed, and a support frame having a rectangular window, wherein the outer shape of the support frame has W-shaped grooves, V-shaped grooves, or chamfered portions in correspondence with the mask pattern magnification correction method of the present invention.
In order to achieve the above objects, the sixth aspect of the present invention is characterized by comprising a pressurizing mechanism which applies, for a mask structure which has a mask substrate on which a mask pattern is formed and a ring-shaped support frame having a rectangular window, forces to four pressurizing points of an outer periphery of the support frame on substantially extended lines of two diagonal lines of the rectangular window, wherein an angle of a vector of each force based on the pressurizing mechanism can be changed with respect to each of the pressurizing points.
In the mask pattern magnification correction apparatus according to the present invention, for at least some of the pressurizing points, pressurizing points may be set for pressurizing in two directions perpendicular to each other, and for at least some of the vectors of the forces, the force may be decomposed in X- and Y-axis directions parallel to sides of the rectangular window and applied to the support frame. The force is preferably applied to the support frame through a rolling contactable portion. Some of the pressurizing points are preferably set as fixed points. For at least some of the fixed points, a slide function is preferably added to a receiving mechanism that receives the fixed point.
The present invention can also be applied to an exposure apparatus which transfers a mask pattern onto a photosensitive substrate on the basis of a mask pattern manufactured using any one of the above mask pattern magnification correction methods or mask pattern magnification correction apparatuses.
The present invention can also be applied to a semiconductor device manufacturing method comprising the steps of installing, in a semiconductor factory, manufacturing apparatuses for performing various processes, including the exposure apparatus, and manufacturing a semiconductor device using the manufacturing apparatuses by performing a plurality of processes. The method preferably further comprises the steps of connecting the manufacturing apparatuses through a local area network, and exchanging information related to at least one of the manufacturing apparatuses between the local area network and an external network outside the semiconductor manufacturing factory by data communication. Preferably, maintenance information of the manufacturing apparatus is obtained by accessing, through an external network, a database provided by a vendor or user of the exposure apparatus by data communication, or production management is done by data communication with a semiconductor manufacturing factory different from the semiconductor manufacturing factory through the external network.
The present invention can also be applied to a semiconductor manufacturing factory comprising manufacturing apparatuses for performing various processes, including the exposure apparatus, a local area network which connects the manufacturing apparatuses, and a gateway which allows the local area network to access an external network outside the factory, wherein information related to at least one of the manufacturing apparatuses is exchanged by data communication.
The present invention can also be applied to a maintenance method for the exposure apparatus installed in a semiconductor manufacturing factory, comprising the steps of causing a vendor or user of the exposure apparatus to provide a maintenance database connected to an external network outside the semiconductor manufacturing factory, permitting access from the semiconductor manufacturing factory to the maintenance database through the external network, and transmitting maintenance information accumulated in the database to the semiconductor manufacturing factory side through the external network.
In the present invention, the exposure apparatus may be characterized by further comprising a display, a network interface, and a computer which executes network software, wherein maintenance information of the exposure apparatus is exchanged through a computer network by data communication. The network software preferably provides, on the display, a user interface connected to an external network outside a factory in which the exposure apparatus is installed to access a maintenance database provided by a vendor or user of the exposure apparatus and allows obtaining information from the database through the external network.
As described above, as the first effect of the present invention, mask pattern correction by different magnifications in the X- and Y-axis directions can also be realized.
As the second effect of the present invention, mask pattern magnification correction can be performed by a mechanism or pressurizing method that is more simple and easy to handle. Hence, the apparatus can be made compact, and the controllability and operability can be improved. In addition, for example, when some pressurizing points are set as fixed points, the apparatus can be made compact because the number of complex pressurizing mechanisms can be decreased. Furthermore, the position of the mask pattern from the fixed points can easily be obtained, resulting in advantage in positioning control.
As the third effect of the present invention, an apparatus and a device manufacturing method, which can accurately correct the mask pattern transfer magnification, can be provided. Hence, devices that are more precise than before can be produced at high yield.
As the fourth effect of the present invention, an apparatus or method, which can correct the magnification in mask pattern drawing, can be provided.
As the fifth effect of the present invention, a mask structure to be subjected to the mask pattern magnification correction method of the present invention can be provided.
Other objects and advantages besides those discussed above shall be apparent to those skilled in the art from the description of a preferred embodiment of the invention which follows. In the description, reference is made to the accompanying drawings, which form a part thereof and which illustrate an example of the invention. Such an example, however, is not exhaustive of the various embodiments of the invention, and, therefore, reference is made to the claims which follow the description for determining the scope of the invention.